| Barroisiceras Temporal range: | |
|---|---|
 | |
| Fossil of Barroisiceras species. Coniacian of Madagascar | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | † Ammonoidea |
| Order: | † Ammonitida |
| Family: | † Collignoniceratidae |
| Subfamily: | † Barroisiceratinae |
| Genus: | † Barroisiceras de Grossouvre, 1894 |
| Subgenera [2] | |
| |
Barroisiceras is an acanthoceratacean ammonite from the Upper Cretaceous, Coniacian, [1] included in the family Collignoniceratidae.
The shell of Barroisiceras is rather involute, coiled such that the outer whorl embraces much of the previous, and is generally compressed. Whorls are high with a strong crenulate keel and sparse umbilical tubercles that develop into pairs of commonly flat ribs.
Barroisiceras is divided two subgenera, Barroisiceras (Barroisiceras) and Barroisiceras (Texasia),with Alstadenites sometimes added as a third, Barroisiceras (Alstadenites). B. (Barroiciceras) is moderately involute and the suture is rather simple. B. (Texasia) is more evolute and has a distinctly eccentric umbilicus and more complex suture.
Cretaceous of Austria, Czechoslovakia, France, Hungary, Italy, Japan, Morocco, Slovakia, Spain, Trinidad and Tobago and USSR [2]
Karamaiceras is an extinct cephalopod genus belonging to the Ammonoidea that lived during the Early Cretaceous. Its shell is involute, smooth and rather compressed, with the outer whorl strongly embracing the inner whorls. Sides are flattish to slightly convex and slope inwardly toward a narrowly rounded venter.
Anahoplites is a genus of rather involute, compressed hoplitid ammonites with flat sides, narrow flat or grooved venters, and flexious ribs or striae arising from weak umbilicle tubercles that end in fine dense ventrolateral nodes. The elements of their sutures are short, wide and jaggedy. Specimens of Annahoplites have diameters typically in the range of 4–6 centimetres (1.6–2.4 in) although some with diameters of as much as 19 centimetres (7.5 in) have been reported. The genus lived during the Cretaceous, from the Middle to the late Albian.
Barremites is an ammonoid cephalopod belonging to the family Desmoceratidae, that lived during the Hauterivian and Barremian stages of the Early Cretaceous. Its shell is moderately to very involute, with the outer whorl strongly embracing the inner whorls, and variably compressed. Sides are generally smooth and marked with sinuous or falcate collars marking intervals of growth and bearing feeble striae to moderately distinguished ribs.
Coilopoceratidae is a family of generally large, proper ammonites with strongly involute shells from the Cretaceous, Albian to Turonian. Coilopoceratids have variably compressed shells with flattish to broadly rounded sides and narrowly rounded to sharp keel-like venters. Whorl sections are generally lanceolate. The suture is ammonitic with an overall clumpy appearance.
Beudanticeras is an extinct cephalopod genus from the Late Cretaceous period; Albian and Cenomanian, belonging to the ammonoid subclass and included in the family Desmoceratidae.
Utaturiceras is an upper Cretaceous (Cenomanian) ammonitid belonging to the family Acanthoceratidae and subfamily Mantelliceratinae.
Ammonitina comprises a diverse suborder of ammonite cephalopods that lived during the Jurassic and Cretaceous periods of the Mesozoic Era. They are excellent index fossils, and it is often possible to link the rock layer in which they are found to specific geological time periods.
Fissilobiceras is a smooth, compressed, involute ammonite from the lower Middle Jurassic of Europe, named by Buchman in 1919. It is assigned to the hildoceratoid family, Hammatoceratidae.
Placenticeras is a genus of ammonites from the Late Cretaceous. Its fossils have been found in Asia, Europe, North and South America.
Exiteloceras is an ammonite genus from the Late Cretaceous.
Oxynoticeratidae is a family of true ammonites included in the superfamily Psiloceratoidea.
Placenticeratidae is an extinct family of mostly Late Cretaceous ammonites included in the superfamily Hoplitoidea, derived from the Engonoceratidae by an increase in suture complexity.
Craspedites is an ammonoid cephalopod included in the Perisphinctaceae that lived during the Late Jurassic and Early Cretaceous, found in Canada, Greenland, Poland, and the Russian Federation.
Lytoceratidae is a taxonomic family of ammonoid cephalopods belonging to the suborder Lytoceratina, characterized by very evolute shells that generally enlarge rapidly, having whorls in contact but mostly overlapping very sightly, or not at all.
Hypophylloceras is a Cretaceous ammonite with a finely ribbed, compressed, involute shell; some having periodic stronger ribs or folds. The suture is complex, with large, asymmetric and finely divided lobes; the 1st lateral being much larger than the external (=ventral) and 2nd lateral lobes. Saddle endings commonly not phylloid.
Hauericeras is an ammonite genus from the Late Cretaceous that lived from the Coniacian to the late Maastrichtian, from about 90 to 66 mya. Fossils have been found in Europe, Russia, South Africa, Australia, India, Iraq, and in the United States.
Lytoceratinae is a subfamily of ammonoid cephalopods that make up part of the family Lytoceratidae.
Neocomites is a genus of ammonite from the Lower Cretaceous, Berriasian to Hauterivian, and type genus for the Neocomitidae.
Parapopanoceras is a ceratitid ammonite with a small, smooth, very involute and moderately globose shell that lived during the middle Triassic.
Holcodiscidae is an ammonite family placed in the Ammonite superfamily Desmoceratoidea.
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